1. Field of the Invention
The present invention generally relates to electrode-electrolyte composites.
2. Background Information
Composite materials offer a wide range of advantages by incorporating materials having different characteristics into a single unit where each material retains its identity while contributing desirable properties to the whole. However, the compatibility of the different materials can cause problems depending upon the environmental conditions exposed to the composite (e.g., chemical reactivity, bonding, cracking, delamination and others).
This incompatibility behavior can be seen, for example, in certain types of fuel cell technology. Fuel cells generally use electrode-electrolyte layered composites comprising a unit cell. A unit cell may suffer from cracking and delamination of the electrode material due to differences in the thermal coefficients of expansion between the electrode and electrolyte materials, and changes in volume due to oxidation/reduction of the electrode materials. In addition, the problem is exacerbated by the fact that fuel cell performance levels may be related to the surface area of the electrode material. Thicker layers of electrode material may provide higher performance, but also may cause more severe cracking and delamination. The subject matter described below addresses this issue.